反应详情

(2-Chloro-6-trifluoromethyl-pyridin-3-yl)-carbamic acid methyl ester: Pyridine (3.98 g, 50.4 mmol) and methyl chloroformate (2.62 g, 27.7 mmol) were added at 0° C. to a solution of 3-amino-2-chloro-6-trifluoromethylpyridine (4.95 g, 25.2 mmol) in dichloromethane (100 ml). The reaction mixture was stirred for 18 h at RT, then cooled to 0° C. and treated with pyridine (3.98 g, 50.4 mmol) and methyl chloroformate (0.95 g, 10 mmol). The reaction mixture was stirred for 24 h at RT and 2.5 h at reflux, then partitioned between ethyl acetate and 10% aq. sodium hydrogencarbonate solution. The organic layer was washed with 10% aq. citric acid solution and brine, dried (MgSO4), and evaporated. Chromatography of the residue (SiO2, heptane/ethyl acetate 4:1) afforded the title compound (4.47 g, 70%). White solid, MS (EI) 219.1 (100), 254.1 (28, M+).

1. temperaturecooled to 0° C.
2. stirringThe reaction mixture was stirred for 24 h at RT and 2.5 h
3. temperatureat reflux
4. custompartitioned between ethyl acetate and 10% aq. sodium hydrogencarbonate solution
5. washThe organic layer was washed with 10% aq. citric acid solution and brine
6. dry with materialdried (MgSO4)
7. customevaporated